摘要:
A head-carrier drum control apparatus in a magnetic recording and/or reproducing apparatus which comprises a rotatably supported head-carrier drum assembly; a drive unit accommodated in the head-carrier drum assembly including a coil, disposed in a magnetic circuit, and at least one positionable magnetic transducing head cooperable with the coil to be displaced in a direction generally widthwise of a length of magnetic tape. The apparatus further includes a contact feeler through which a control current is supplied to the drive unit; an electrode held in contact with the contact feeler and connected electrically with the coil; and a drive circuit for controlling the position of the transducer head so as to cause a trace of movement of the transducing head depicted during information reproduction to properly follow a track recorded by a magnetic transducing head on the length of magnetic tape during information recording.
摘要:
A process for producing polyethylene of ultrahigh molecular weight having an intrinsic viscosity of 10-30 dl/g at 135.degree. C. in decalin is disclosed which comprises at least the following two stages of polymerization reaction: (a) a first reaction stage where in ethylene is polymerized with use of a catalyst comprising a solid component containing at least Mg, Ti and/or Va and in the absence or presence of hydrogen of reduced concentration to produce 70-99.5 weight parts of polyethylene having an intrinsic viscosity of 12-32 dl/g at 135.degree. C. in decalin; and (b) a second reaction stage wherein a fresh feed of ethylene is polymerized in the presence of hydrogen of higher concentration to produce 30-0.5 weight parts of polyethylene having an intrinsic viscosity of 0.1-5 dl/g at 135.degree. C. in decalin.
摘要:
A catalyst for polymerization of olefins is disclosed which comprises a titanium and/or vanadium compound supported on a silicon and/or aluminum oxide carrier. This carrier has peculiar characteristics including a specified proportion of highly spherical oxide particles, a selected average pore size and a specified proportion of a selected particle size range before and after ultrasonic treatment, whereby there is obtained a catalyst having increased bulk density, narrow particle size distribution and high fluidity.
摘要:
The present invention provides an ultra-high-molecular-weight polyethylene solution which is produced by the steps of subjecting a kerosene fraction having a boiling point of 160.degree. to 300.degree. C. to a nucleus hydrogenation treatment at a pressure of 30 to 100 kg/cm.sup.2 at a temperature of 100.degree. to 300.degree. C. in the presence of a metallic catalyst for nucleus hydrogenation of aromatic nuclei; separating and removing at least a part of n-paraffins present in the kerosene therefrom by the use of a molecular sieve made up of a synthesized zeolite in order to obtain a residual oil; fractionating the latter by a rectification apparatus to obtain a hydrocarbon mixture fraction which has a boiling point of 180.degree. to 250.degree. C. and which is substantially free from naphthalene and biphenyl; and dissolving, in the hydrocarbon mixture fraction, an ultra-high-molecular-weight polyethylene having an intrinsic viscosity of 8 or more in decalin at 135.degree. C.
摘要:
A batch-operated furnace apparatus for manufacturing powdered silicon nitride comprises a reaction furnace having a reaction chamber, an upper portion, a bottom portion and a side portion, a feed pipe placed at the upper portion of the reaction furnace for feeding starting materials in a fine or coarse particle form, an exhaust pipe placed at the upper portion of the reaction furnace for removing gasses from the reaction chamber, a gas distributor plate positioned at the bottom portion of the reaction chamber for introducing nitrogen gas into the reaction chamber so as to form a fluidized bed at the bottom portion of the reaction chamber, a heater for heating the starting materials of the fluidized bed within the reaction chamber, a discharge port formed in the gas distributor plate, a discharge pipe joined to the discharge port of the gas distributor plate, a valve seat formed at the discharge port, a discharge valve means having the valve which engages the valve seat of the discharge port, and a guide tube provided at an upper portion of the reaction furnace. The discharge valve means extends through the guide tube in a vertical direction in such a way that the valve of the discharge valve means selectively contacts the valve seat of the discharge port thereby to open or close the discharge port.
摘要:
An etalon includes a fixed mirror disposed on a first substrate, a movable mirror disposed on a second substrate to face the fixed mirror with a gap interposed therebetween, a first electrode disposed on the surface of the first substrate facing the second substrate, a second electrode disposed on a first surface of the second substrate facing the first substrate and separated from the first electrode, and a warp preventing film disposed on a second surface of the second substrate so as to cover at least the movable mirror in a plan view. The direction of an internal stress acting in the in-plane direction of the warp preventing film is parallel to the direction of an internal stress acting in the in-plane direction of the movable mirror and the second electrode.
摘要:
A tunable interference filter comprising a first substrate, a second substrate facing the first substrate, a first reflection film formed on the first substrate, a second reflection film formed on the second substrate, the second reflection film facing the first reflection film by interposing a gap, and a gap adjustable-part that adjusts the gap, wherein the second substrate has a first surface and a second surface opposed to the first surface, wherein the second substrate includes a first groove on the first surface, and wherein the second substrate includes a second groove on the second surface, the second groove facing the first groove.
摘要:
A selection criterion appropriate for searching for a web service in UDDI. A provider that provides web services collects result information, which will be used to judge the quality of provided web services, and sends the information to a UDDI site). The UDDI site manages this result information and, in response to a web service search request from a requestor, returns a searched web service and result information on the web service.
摘要:
A variable wavelength interference filter includes: a first reflective film disposed on a face of a first substrate facing a second substrate; a second reflective film disposed on a face of the second substrate facing the first substrate and the first reflective film; a first electrode disposed on the face of the first substrate; and a second electrode disposed on the face of the second substrate. The second substrate includes a movable portion on which the second reflective film is disposed and a connection maintaining portion maintaining the movable portion to be movable in a substrate thickness direction, the connection maintaining portion circumscribes the movable portion and is thinner than the movable portion, and the second electrode is disposed on a portion of the second substrate that is thicker than the connection maintaining portion.
摘要:
An etalon is provided with a fixed substrate and a movable substrate opposed to the fixed substrate. The fixed substrate is provided with a first bonding surface to be bonded to the movable substrate via a bonding film and a first electrode surface on which a part of the first electrode is formed. The movable substrate is provided with a second bonding surface to be bonded to the first bonding surface via the bonding film and a second electrode surface on which a part of the second electrode is formed. In the state in which the fixed substrate and the movable substrate are bonded to each other with the bonding film, the first electrode formed on the first electrode surface and the second electrode formed on the second electrode surface have contact with each other.